package com.internet;

import org.junit.Test;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * 实现TCP的网络编程
 * 例子1: 客户端发送信息给服务端，服务端将数据显示在控制台上
 */
public class TCPTest1 {


    //客户端
    @Test
    public void client() throws IOException {

        //1.创建Socket对象，指明服务器端的ip和端口号
        InetAddress inetAddress = InetAddress.getByName("127.0.0.1");
        Socket socket = new Socket(inetAddress, 8899);

        //2.获取一个输出流，用于输出数据
        OutputStream outputStream = socket.getOutputStream();

        //3.写出数据的操作
        outputStream.write("你好，我是客户端".getBytes());


        //4.资源的关闭
        outputStream.close();
        socket.close();

    }


    //服务端
    //服务端一直开启就好
    @Test
    public void server()  {
        ServerSocket serverSocket = null;
        Socket socket = null;
        InputStream inputStream = null;
        ByteArrayOutputStream byteArrayOutputStream = null;

        try {
            //1.创建客户端的ServerSocket,指明自己的端口号
            //接收客户端数据
            serverSocket = new ServerSocket(8899);

            //2.调用accept()表示接收来自客户端的socket
            //接收客户端的套接字，socket
            socket = serverSocket.accept();

            //3.获取输入流
            inputStream = socket.getInputStream();

            //不建议这样写，可能会有乱码
//        byte[] buffer = new byte[20];
//        int len;
//        while ((len = inputStream.read(buffer)) != -1) {
//            String str = new String(buffer, 0, len);
//            System.out.print(str);
//        }
            //这里面有一个动态数组 4.读取输入流中的数据
            byteArrayOutputStream = new ByteArrayOutputStream();

            byte[] buffer = new byte[5];

            int len;
            while ((len = inputStream.read(buffer)) != -1) {
                byteArrayOutputStream.write(buffer, 0, len);
            }

            System.out.println(byteArrayOutputStream.toString());
            //获取客户端ip
            System.out.println("收到了来自于:" + socket.getInetAddress().getHostAddress() + "的数据");

            String s = "xuehu";

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            //5.进行资源的关闭
            if(byteArrayOutputStream != null) {
                try {
                    byteArrayOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if(inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if(socket != null) {
                try {
                    socket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if(serverSocket != null) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            }
        }


        //都必须使用try-catch，这里图省事，使用了throws
        //关闭资源,从下而上的顺序关闭







    }

}
